Apparatus for heat-treating metals



it Patented Apr. 11, 1930 "unnao {ST/A TES- HARRY BENTON PIPER, OF CH ICA.G0, ILLINOIS, ASSIGNOR T WESTERN ELECTRIC COMPANY INCORPORATED, OF NEW'YOBIK, N. Y., A CORPORATION OF NEW YORK APPARATUS FOR HEAT-TREATING METALS Application filed November 14, 1922, Serial No. 600,864. Renewed Ju1y'28, 1927.

This invention relates to apparatus for heat treating metals. An object of the invention is to provide such an apparatusin which the heating and cooling of the-metal may be continuously per. formed and the temperatures. of the heating and cooling regulated within close limits.

Another object of the invention resides in an improved means for conducting heat away fromthe metal subsequent to its subjection to the heating means.

The apparatus herein disclosed is particularly adapted for'heat treating a copper wire to be used as an electrical conductor for. the m transmission ofintelligence, the conductorbeing wrapped with a metallic alloy tape having certain electrical characteristicswhich are controlled to some extent by the character of the heat treatment administered thereto. A full disclosure of the metallurgical constituency' of the tape or of its electrical char-- acteristics or of the specific heat treatment P are not necessary to a complete understanding-o f the present invention which is not. :5 limited to this use but may be employed for '1' other purposesland the invention isonly to'be limited by theisp'irit .and scope of the apded claims.

Other objects, features, and advantages of $0 the invention will be set forth in detail in the following description'andparticularly point ed out in the claims.

' In the accom anying drawings which illustrate one embo iment of the invention,

Fig. 1 is a side elevation partly broken away,,il;lustrati ng an apparatus made in accordance with the invention;

Fig. 2 .is an enlarged vertical sectional view the, left hand end of the cooling tube; Fig; 3'is an enlarged 'fragmentary verti cal sectional view of the cooling tube; Fig. 4 is a vertical sectional -viewtaken on the line H of. Fig. 3; and

Fig.5 is an enlarged fragmentary side elevation showing the exit end of the tube through which the strand is fed.

- Although the apparatus disclosed in the drawing is particularly designed for heat treating metal in strand form, it is to be understood that the apparatus maybe modified to treat metal in other forms, without departing from the spirit and scope of the invention.

Referringmow to the drawings in detail in which like reference numerals designate similar parts throughout the several views:

Numerals 10 and 11 indicate two furnaces which are in juxtaposition. These furnaces may be of any suitable type and heated in any desired manner. They are illustrated as be- 'ing electric furnaces heated by coils diagrammatically illustrated at 12'and 13 respectives ly. The furnacelO is longer than the furnace 11 and is maintained at a higher temperature,

the purpose of which will be hereinafter e X- lained. Insteadof two furnaces, it is to be understood that a single furnace havingtwo zones maintained at different temperatures may be utilized, or the heating means otherwise modified, without departing from the spirit and scope of the invention. a

Suitably suppogted within the furnaceslO and 11 is a metallic tube 14: which communicates with a cooling tube 15, as shown in Fig. 2. he strand to be heat treated is fed from a supply reel. 16 over a suitablecurved guide 17 and pushed through the tubes 14 and 15 by means of a caterpillar feeding mechanism .18. Asthe strand passes from the discharge end of the cooling tube 15, it is acted upon by a" second caterpillar feedin mechanism 19, which serves to take up slack 1n the strand, the heat treated strand being taken up on a storage reel 20. For a detailed illustration 7 and description of the construction and operation'ofthe caterpillar mechanisms 18 and 19,, reference vis made to the Patent No. 1,653,215, issued to Frederick S. Kochendorfor and A. E. Schulz, on December 20, 1927. For the sake of simplicity the drawings only illustrate one heating tube and one cooling tube, but it is to be understood that in practice a plurality of tubes similar to the tube 14. maybe mounted within the furnaces and 11 and that a' plurality of cooling tubes 15 maybe utilized therewith. The caterpillar feeding mechanisms are designed to receive five strands so that this number of heating and cooling "tubes may be utilized without necessitating any modification in thel oeding mechanism.

In the heat treatment ofthe metallicvallo tape heretofore referred to, it has been found desirable to relatively graduallyheat the tape to apredetermined temperature, ma ling:

tain the tape at or above this temperaturefor a certain time'interval and then reduce the temperature-of the tape to a predetermined degree within a certain period of time. Since the apparatus disclosed is particularly designed for performing this heat treatment, the furnace 10. is heated to a-degree slightly higher than the temperature at which it is desired to maintain the tape for the predetermined length of time, the tape lea-vino the furnace llland entering the furnace 11 which is kept at the temperature at which it 15 desired to maintain the'tape for a certain length of time. By heating the furnace, 10 to a degree slightly above that atwliich it is desired to maintain the tape, it is possible to keep the tapeat an even predetermined temperature. 'The furnace lO is made considerably longer than the furnace ll in'order that the tape may beralsed to the required temperature during its passage through the furnace,

the length of the furnace 1O determining the speed at which the conductor having the tape wrapping may be drawn therethrough. Since the tape is at approximately the desired temperature when it enters the furnace 11, this furnace may boot a length just su ficient to maintain the tape at the desiredh eat for the desired length of time. i

For a full discl-osure'of the composition of the alloy tape, its application to the condu'ctor and the subsequent heat treatment, reference is made to the patents to Gustaf W. Elmen,

No. 1,586,884, issued June 1, 1926; OliverE.

Buckley, No. 1,586,874 issued June 1,1926;

- and Gustaf W. Elmen, No. 1,586,887, issued June 1,1926. The heating tube 1 1 and cooling tube-15' are connected b a short length of tubing 21 (Fig. 2), The eating tube 14; and connecting tube 21 are the same diameter and are ex ternally screw threaded within collars 22 and 23 respectively, so as to abut each other, the said collars being connected together by bolts 24. The connectingtube 21 is of smaller diameter than the cooling tube 15 and is extornally screw threaded to mesh with internal screw threads in the cooling-tube. Threaded upon the outside of'the cooling tnbe15 and the conneetingtube 21 is a plug 25 having an external screw threaded flange 26 upon which a pipe 27 concentric with the cooling tube 15 is threaded. The thickness of the flange 26 spaces the pipe 27 and cooling tube 15 .apart so as-to form a tubular chamber" 28 between them. chamber 28 is cldse'd by a suitable plug 29 (Fig. I), having, an opening through which the end of the cooling tube projects. A suitable cooling-fluid such as water oroil is constantlycirbu'lated through-the chamber 28 entering by 'a pipe'30 and beingdisicharged through a pipe 31, the said fluid being circulatedby a pump or other suitable 'ineans (not shown). In 'order'to insure a -1thorough" circulation of the cooling fluid.

around the cooling tube, a coil spring 32'is fitted within the chamber 28 surrounding 'thecooling tube, the spring forming a tor-1 tuous passage through which the cooling fluid, is 'forced from the entrance pipe 30120 the exitpipe 31. The conductor 1, in being pushed and pulled through the heating tube 141.- and cooltion 'oftlie heat from the conductor to the inner peripheral surface of the cooling tubei 15, a plurality of heat conducting bars 33 constructed of copper or other suitable metal of high "heat conductivity are placed within the coolingtubein 'endto end relation, as' shown in Fig. 3. The members 33 fit rela- The other end of the 'ing tube 15 lies'on the bottom thereof, 'shownin Fig. 2. In order to promote radiatively loosely within the cooling tube'and (Fig 4:), embracing the conductor ,1. ln order to keep the grooves 3-1 in alignment, the

members'33 are prevented from turning, one

are provided with a triangular groove 34% relative to the other, by meansot dowel pins 35. Theconductor passes through the cool ing ,tube 15 in the direction indicated by the arrow (Fig; 3) and the frictional contact between the members 33 and the conductor tends to pull the said members out of'the cooling becomes too great, the said members will be drawn out of the ,cooling tube against the action of the spring retaining member '36.

Due to this construction, friction between the heatconducting members and the conductor,

which might tend to place undue tension on 1 the conductor is prevented. In depositing the'heat conducting members 33 within the cooling tube '15 they are inserted into the latter through the exit end thereof, one after the other, the insertion of each member push.-

lBO

ing the one in advance of it farther into the cooling tube, as is readily understood.

By providing the heat conducting members 33, a rapid radiation of heat from the conductor is accomplished, and by mounting them in the manner above described, all undue friction between them and the cooling tube is prevented. Should the cooling. tube be made to relatively closely fit the conductor, although rapid radiation of the heat from the conductor might be accomplished, should the taped conductor vary in diameter so as to ress against the inner periphery of the coolmg tube, the entire conductor might be subjected to undue tension.

In the heat treatment of the metal alloy tape heretofore mentioned, it has been found desirable to subject the conductor and the tape wrapping to as little tension as possible during the heat treatment, and for this reason the construction of cooling tube, above described, is provided. This'construction, however, may be found desirable in the heat. treatment of other metals, and the invention is not to be limited to its use inconnection with the metallic tape above referred to, but only in so far as is defined in the appended claims.

In order to provide both a non-oxidizing and a non-reducing atmosphere in the heating tube 1 1-, nitrogen under pressure isforced into the said tube through' a pipe 37, screw threaded in the collar 22, which is provided with a passage 40 formed at an'an le so as to direct the gas into the heating to e 14, and in a direction opposite to that in which the material being treated is moving. The nitrogen entering through thepipe 37 is forced into the heating tube 14, and provides both a non oxidizing -and non-reducing atmosphere, and in its passage through the tube sweeps out any other gases that may be presenttherein.

What is claimed is: v

1. An apparatus for processing material subsequent to heat treatment comprising inner and outer receptacles, the inner receptacle supporting and physically engaging the material for substantially the entire length of the receptacle, a heat conducting metallic member within the inner receptacle also en gaging the material, and a cooling fluid in the outer receptacle for conducting the heat from said inner receptacle and said metallic element as received from said material.

2. In a treating apparatus for metals in strand form; a cooling chamber, means for feeding the strand through said chamber, said cooling chamber comprising a receptacle to '1 receive the strand, a heat conducting member loose within said receptacle and engaging the strand, and means of such character retaining the heat conducting member within said receptacle that predetermined frictional contact between the strand and the member will draw the latter out of the receptacle as the strand is fed therethrough. 3. In a treatingv apparatus for metals in strand form, a cooling chamber, inner and outer receptacles, a cooling fluid within the outer receptacle, the inner receptacle adapted to receive the strand, means for feeding the strand through the chamber, a metallic heat conducting member loose within said inner receptacle and engaging the strand, and means of such. character retaining the heat. conductingfmember within said receptacle that predetermined frictional Contact between the strand and themember will draw the. latter out of the receptacle as the strand is fed therethrough.

4. In a treating apparatus for metals, a

cooling chamber comprising an inner'receptacle to receive the metal, an outer receptacle, a heat conducting member in said receptacle contacting with said metal, a cooling medium in the outer receptacle, and means for causing said cooling medium to flow in a tortuous path through said outer receptacle to conduct away the heat received from said metal.

6. In a treating apparatus for metals,. a cooling chamber comprising a receptacle to receive the metal, and a heat conducting mem-' ber mounted loosely within said receptacle to permit its movement in accordance with variations in the dimensions of the metal being treated and provided with an inverted V-shaped groove along which said metal is advanced.

7. In a treating apparatus for metals, a cooling chamber comprising a receptacle supporting the treated metal and in direct contact therewith, a heat "conducting member smaller than the interior cross-sectional dimension of the receptacle topermit its move ment transversely of the receptacle upon the occurrence of any variation in the dimensiouof the metal being treated and provided with a groove along. which the metal is advanced and the walls thereof engage for conducting heat from said metal.

8. In a treating apparatus formetals subsequent to heat treatment comprising a receptacle supporting the treated metal, a heat conducting member contained in said receptacle and engaging the metal for the purpose of conducting heat therefrom, an outer receptacle, and a helical member positioned in said outer receptacle for causing a cooling medium to flow in a tortuous path from said outer rec ceptacle.

9. In a treating apparatus for metals a cooling chamber comprising an inner recep-- tacle to receive the metal, a plurality of lengths of a conducting element in abutting relation and pinned to each other engaging said metal, an outer receptacle, and means in the outer receptacle for causing a cooling me- (lium to How in a tortuous path for conducting the heat- :t'rom said inner receptacle and the conducting element.

In Witness whereof, I hereunto subscribe lny naine this -J-th (lay of Nov. A. D. 1922.

HARRY DENTON PIPER. 

